Untar, ungz, gz, tar - how do you remember all the useful options?

Question

I am pretty sure I am not the only one with the following problem: every time I need to uncompress a file in *nix I can't remember all the switches, and end up googling it, which is surprizing considering how often I need to do this.

Do you have a good compression cheat sheet? Or how about a mnemonic for all those nasty switches in tar?

I am making this article a wiki so that we can create a nice cheat sheet here.

Oh, and about man pages: is there's one thing they are not helpful for, it's for figuring out how to uncompress a file.

Solution 1

Or how about using the shell with advanced completion capabilities (like zsh or fresh versions of bash) which will complete the options for you, with comprehensive help? :))

Regarding tar: just look at the "qwerty" keyboard. There are letters "zxcvf" next to each other. You need either "tar czvf file.tar.gz files" or "tar xzvf file.tar.gz".

Solution 2

Tar option summary

Y'all are welcome to edit this to add more esoteric switches but here are the basics:

• x - extract files
• c - create archive
• t - list files
• v - verbose (list files as it processes them)
• j - use bz2 compression
• z - use gz compression
• f - read or write files to disk

Examples

Uncompress a tar.gz file: tar zxf tarball.tar.gz

Uncompress a tar.bz2 file: tar jxf tarball.tar.bz2

Create a tar.gz file: tar zcvf tarvall.tar.gz mydir/*

Solution 3

There's a small Perl script called "unp".

unp filename.tar.gz

...and it extracts everything. Works with any compressed file as long as you have the right binaries. And you just forget about syntax or any of that crap. Check your Linux distribution's repositories. It should be there (at least on Arch, Debian and Ubuntu).

Solution 4

Really with a frequent usage I make difference between extracting (x) data and compressing (c) data:

To extract:

tar xzf data.tgz

To compress:

tar czf data.tgz

Furthermore you can add two functions too your .bashrc :

function extract () {     
        if ($# -ne 1); then
                echo "Usage: $0  `<compressed archive>"`
                exit 1
        fi
        tar xzf $1
}

function compress () {
        if ($# -ne 2); then
                echo "Usage: $0 `<compressed archive> <files|directories>"`
                exit 1
        fi
        tar czf $1 $2
}

There is another nice extract function, it detect the extension of your compressed file and do the job for you:

extract () {
   if [ -f $1 ] ; then
       case $1 in
           *.tar.bz2)   tar xvjf $1    ;;
           *.tar.gz)    tar xvzf $1    ;;
           *.bz2)       bunzip2 $1     ;;
           *.rar)       unrar x $1       ;;
           *.gz)        gunzip $1      ;;
           *.tar)       tar xvf $1     ;;
           *.tbz2)      tar xvjf $1    ;;
           *.tgz)       tar xvzf $1    ;;
           *.zip)       unzip $1       ;;
           *.Z)         uncompress $1  ;;
           *.7z)        7z x $1        ;;
           *)           echo "don't know how to extract '$1'..." ;;
       esac
   else
       echo "'$1' is not a valid file!"
   fi
 }

Solution 5

Just type tar --help and there's your cheatsheet.

View more solutions

Comments

[Florenz Kley]

use the manual pages, then you don't have to create a wiki, and only have to remember the man command :-) man(1)

[Canadian Luke]

eXtract Zee File is how I remember it

[CousinCocaine]

Create Zee Vocking File might be appropriate for creating a .tar.gz

[deadprogrammer]

seriously, have you ever tried reading that man page?

[Paige Ruten]

It might be a bit unreadable and long but I think it works well for just looking up the name of an option. You can also grep for the option you're looking for, i.e. 'tar --help | grep extract'.

[deadprogrammer]

really? how would you deduce tar -xvf from this?

[pxl]

You should get in the habit of always providing the f option: it's only recently that distributions of tar default to f -, the historical default is f /dev/rmt0 or similar. After all, tar is the Tape ARchiver.

[Admin]

Great. And then you have to wade through a man-page that (among the stuff you are looking for) tells you tons of archaic streamer commands and options noone except the developer needs.

[Paige Ruten]

Well it seems to work for me (with tar as well as other ocmmand-line linux programs). I just use the '--help' option or 'man' and scan for the information I need, and that's always worked well for me. If there's too much useless information I just skip over it.

[Admin]

Now, that is a COOL "qwerty" tip! :)

[deadprogrammer]

fricking awesome!

[Paige Ruten]

I really don't see what's so hard about it. To extract an archive, just find the extract option and add -x to your command. If you want it verbose, find that option and add a v to get -xv. Then continue until you get the exact command you want. It even has example commands for common operations.

[Andrew Grimm]

Until now, I've been using fileroller, but currently I'm out of luck because the version I have uses 1.1 Gb of memory.

[Nate]

Another tip is that the z option (or the j option for .bz2 files) is not needed when extracting with modern versions of tar. It automatically uncompresses the file.

[Tyler McHenry]

I've used tar about ten billion times and never noticed that all the most commonly used options are right next to each other on the keyboard. headsmack

[Nazadus]

Jeremy, the real problem is you may not always know the proper vocabulary. As such, it's easy to get confused and find similar options and have them not work. Then, you have to place (some) of them in proper order. This is non-trivial for someone migrating away from Windows. Even more-so if they didn't know scripting in Windows.

[Claudiu]

i just memorized the easy to remember ditty - "ex vee vee zee eff"! but yeah i never could remember how to make an archive

[Claudiu]

whats tabulating?

[iacnats]

Even after using tar for quite a long time I still need to google for the stupid flags. unp is the way to go.

[Maxim]

One tip is that recent version of tar detect the format automatically on extract so you can just use -x to extract.